RE: Intel timed i/o driver in HTE

[N, Pandith]

> -----Original Message-----
> From: Linus Walleij <linus.walleij@xxxxxxxxxx>
> Sent: Thursday, November 24, 2022 2:53 AM
> To: N, Pandith <pandith.n@xxxxxxxxx>
> Cc: Dipen Patel <dipenp@xxxxxxxxxx>; linux-kernel@xxxxxxxxxxxxxxx; Hall,
> Christopher S <christopher.s.hall@xxxxxxxxx>; Gross, Mark
> <mark.gross@xxxxxxxxx>; Sangannavar, Mallikarjunappa
> <mallikarjunappa.sangannavar@xxxxxxxxx>; D, Lakshmi Sowjanya
> <lakshmi.sowjanya.d@xxxxxxxxx>; T R, Thejesh Reddy
> <thejesh.reddy.t.r@xxxxxxxxx>; andriy.shevchenko@xxxxxxxxxxxxxxx;
> timestamp@xxxxxxxxxxxxxxx
> Subject: Re: Intel timed i/o driver in HTE
> 
> On Wed, Nov 23, 2022 at 3:38 PM N, Pandith <pandith.n@xxxxxxxxx> wrote:
> 
> > Since the current gpio framework is inadequate to periodic output modes.
> > I thought to disentangle from gpio and develop a new hte consumer.
> > Something like hte-libcdev.c
> 
> Maybe, if Dipen wants it.
> Or maybe it needs its own subsystem.
> Or maybe it should be with whatever is using these pulse trains.
> 
> Again: what is it used for? If we have no idea what it is supposed to be used
> for, we cannot place it right, even less test it.
> 
Intel  timed i/o is mainly intended for couple of functionalities.

1. Input event capture with timestamping 
2. Generate single shot or periodic pulse train

Use cases :
a. This has multiple uses like capturing trigger time and event count
b. Calculate periodicity in case of periodic signal on input pin 
c. Most importantly, precise time synchronization between devices/sub-systems 
Ex : Share precise time from a GPS receiver to the network or
       Synchronize processor clock with external signal.

> Yours,
> Linus Walleij

Regards,
Pandith